The results of Electoral College will be officially declared on January 6 in a joint session with the Congress.
Usually, the voting is given little importance, with electors officially casting votes for the candidate that won the popular tally in their state.
However, amid allegations of rigging to Russian interference in the 2016 elections, the votings were thought to give a clear winner.
Democratic activists protested and urged Republican electors to break ranks and refuse to vote for him.
To prevent Trump from becoming president, the protesters needed to persuade at least 37 Republican electors to not vote for Trump.
However tables turned with four Democratic electors voting for someone other than Clinton, the New York Times tally indicated.
Texas upped the votes in Trump's favour with 36 out of 38 votes being cast for him.
Two Republican electors did not cast their votes for Trump.